超塑性气压胀形测控系统的设计与实现.pdf

南京航空航天大学
硕士学位论文
超塑性气压胀形测控系统的设计与实现
姓名:唐黎明
申请学位级别:硕士
专业:材料加工工程
指导教师:童国权
20060101
南京航空航天大学硕士学位论文
摘要

超塑性气压胀形类似于塑料的吹塑成形和真空吸塑成形,是超塑性
在板材成形加工中的典型应用,研制先进的测控系统对于进一步的实验
研究和生产应用都具有重要意义。
本文在有限元及数值仿真研究成果和测控系统研究成果分析的基础
上,提出了一种实现超塑性气压胀形的方案:通过有限元或数值仿真软
件,模拟气压胀形过程,充分考虑工艺条件,通过工艺和参数的调整,
获得最佳的成形零件,将该过程的曲线转化为数据文件格式,通过
测控程序,用于超塑性气压胀形过程的控制。
依据该方案研制了一种超塑性气压胀形测控系统,该系统以计算机
为上位机,完成数据处理和过程监控, 为下位机,完成气压胀形的
数据采集和过程控制,两者之间通过串行通信实现数据交互,共
同组成一个比较完善的测控系统。该系统充分发挥了计算机和的优
点,可以适应不同材料不同工艺参数的超塑性气压胀形过程。
本文首先根据控制学理论和的工作方式,分别提出了系统的组
成方案和控制方案。然后根据系统需要实现的功能,进行硬件选型和软
件设计。最后,连接硬件组成系统,对软件进行一系列的调试,满足了
系统的设计目标。
关键词:超塑性气压胀形,测控系统, 串行通信,数据交互,
小流量调节阀







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超塑性气压胀形测控系统的设计与实现
Abstract

Superplastic bulging is a typically application for superplastic forming
of a blank of material into a part. It is similar to blow molding and vacuum
forming. Developing advanced automatically controlling apparatus is very
important both in further research and production application.
This paper provides a method and apparatus for automatically
controlling the pressure based on the pressure-time relationship during
superplastic bulging. The method is constituted of three parts: determining
relationship between time and pressure system by FEM and numerical
simulation, automatically controlling pressure system and data exchanging
system. Based on this method, a brand new superplastic bulging apparatus is
developed with Programmable Logic Controller puter. PLC is used
as main control unit to automatically control the pressure in accordance
with the previously determined relationship between time and pressure
during the part is formed. Computer is used to deal with data-processing
and data-transmission. Data are exchanged between them through RS-232
munication. This apparatus will be suitable for many kind of
Superplastic Bulging.
This paper mainly discusses three aspects. Firstly, based on the theory
of eng